Set the default outbound SMS number

Outbound SMS — proactive messages from automations, agent-initiated texts, or replies in a thread that doesn’t have a clear inbound number — needs a sender. The default outbound number is the fallback used when no other context picks one.

Before you start

• At least one SMS number assigned to your tenant. The number must be listed in Settings → SMS under Assigned Phone Numbers.
• A decision about which number customers should see as the sender of proactive messages — typically the one that maps to your main brand or market.

Steps

1. Open Settings → SMS.
2. Find the Default Outbound Number dropdown near the top of the page.
3. Pick a number from the list. Each entry shows the friendly name and the phone number itself, for example “Support (+1-555-0123)”.
4. Save.

Outbound messages that don’t otherwise specify a sender will now use this number.

How sender selection works

The default outbound number is the fallback. Atender picks the sender in this order:

1. If the message is a reply on an existing conversation, the conversation’s own number is used (so the customer sees the same number throughout the thread).
2. If an automation or API call explicitly sets a from number, that is used.
3. Otherwise, the default outbound number is used.
4. If the default is set to No default, the team-routing fallback applies — agents on a team-routed number send from that team’s number.

Verify it worked

The cleanest test is to send a proactive SMS from an automation or via the API and confirm the message lands on the customer’s phone from the configured default number.

You can also verify visually: open any conversation that doesn’t already have a number context, click to compose a reply, and the From dropdown (if present) should default to the number you picked.

When to keep “No default”

Setting No default is the right choice when:

• Different teams should always send from their own routed number, never from a shared default.
• You operate in markets where mismatched country codes between sender and recipient would be a problem and you want to force explicit sender selection.

In both cases, leave the default unset and rely on per-team or per-automation sender selection.

Troubleshooting

• Symptom: The Default Outbound Number dropdown shows “No SMS numbers available.” Fix: No numbers are assigned to your tenant yet. Contact your account team to have at least one SMS number assigned.

• Symptom: A proactive SMS sent from an automation arrived from a different number than the default. Fix: The automation likely sets an explicit sender. Open the automation’s action configuration and check the from setting — it overrides the tenant default.

See also

• The SMS channel
• Route an SMS number